How do you determine atomic size?
Periodic Trends of Atomic Radius
An atom gets larger as the number of electronic shells increase; therefore the radius of atoms increases as you go down a certain group in the periodic table of elements.
In general, the size of an atom will decrease as you move from left to the right of a certain period.
What's the atomic size?
The atomic radius of a chemical element is a measure of the size of its atoms, usually the mean or typical distance from the center of the nucleus to the boundary of the surrounding cloud of electrons.
